Under the influence of direct current (DC) voltage, the surface of composite insulators composed of silicone rubber material tends to accumulate surface charges. The presence of these surface charges results in a substantial reduction in surface flashover voltage. In this study, we examine the impact of various parameters on the adhesion and accumulation characteristics of charged particles on the surface of a two-dimensional silicone rubber sheet skirt model, utilizing finite element analysis software. Our findings indicate that as the applied voltage level, relative dielectric constant, and surface conductivity of the material increase, both the surface charge density and charge distribution become more substantial. Moreover, the influence of the material’s properties appears to be more significant than that of the voltage. The pertinent findings presented in this study offer valuable insights for the design and fabrication of composite insulators, contributing to the advancement of this field.